Polymer ammunition having a primer insert with a primer pocket groove

Abstract

The present invention provides an polymer ammunition having a primer insert having a top surface opposite a bottom surface and a extraction flange that extends circumferentially about an outer edge of the top surface; a coupling element that extends from the bottom surface, wherein the substantially cylindrical coupling element is adapted to receive a polymer overmolding; a primer recess in the top surface that extends toward the bottom surface, wherein the primer recess comprises a recess bottom and a circular recess side wall; a primer flash aperture through the recess bottom that extends through the bottom surface, wherein the primer flash aperture is adapted to receive a polymer overmolding to form a flash hole; and a groove in the primer recess positioned around the primer flash aperture adapted to receive a polymer overmolding, wherein the groove extends at least partially over the bottom surface and the groove is adapted to receive polymer at least partially over the bottom surface.

What is claimed is: 
     
       1. A polymeric ammunition comprising:
 a primer insert comprising: a top surface opposite a bottom surface and a extraction flange that extends circumferentially about an outer edge of the top surface; a coupling element that extends from the bottom surface, wherein the substantially cylindrical coupling element is adapted to receive a polymer overmolding; a primer recess in the top surface that extends toward the bottom surface, wherein the primer recess comprises a recess bottom and a circular recess side wall; a primer flash aperture through the recess bottom that extends through the bottom surface, wherein the primer flash aperture is adapted to receive a polymer overmolding to form a flash hole; and a groove in the primer recess positioned around the primer flash aperture adapted to receive a polymer overmolding, wherein the groove extends at least partially over the bottom surface and the groove is adapted to receive polymer at least partially over the bottom surface; 
 a substantially cylindrical polymeric middle body extending about the primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers an circumferential surface of the primer flash hole aperture; 
 a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet; 
 a propellant at least partially filling the powder chamber; 
 a primer inserted into the primer recess; and 
 a bullet frictionally fitted in the bullet-end aperture. 
 
     
     
       2. The polymeric ammunition of  claim 1 , further comprising a diffuser positioned in the primer recess in contact with the primer and comprising a diffuser flash hole aligned with the primer flash hole. 
     
     
       3. The polymeric ammunition of  claim 1 , wherein the middle body connection end is a male coupling element with a straight skirt interlock surface that tapers to a smaller diameter at the forward portion on the skirt tip to mate with a female coupling element of the substantially cylindrical polymeric bullet-end. 
     
     
       4. The polymeric ammunition of  claim 1 , wherein the groove extends about half the distance from the primer flash aperture to the circular recess side wall. 
     
     
       5. The polymeric ammunition of  claim 1 , wherein the groove extends about one third the distance from the primer flash aperture to the circular recess side wall. 
     
     
       6. The polymeric ammunition of  claim 1 , wherein the groove extends about two third the distance from the primer flash aperture to the circular recess side wall. 
     
     
       7. The polymeric ammunition of  claim 1 , wherein the groove extends to about the circular recess side wall. 
     
     
       8. The primer insert of  claim 1 , wherein the primer insert comprises a groove texture. 
     
     
       9. The polymeric ammunition of  claim 1  wherein the polymeric ammunition cartridge has a caliber selected from .223, .243, .25-06, .270, .300, .308, .338, .30-30, .30-06, .45-70 or .50-90, 50 caliber, 45 caliber, 380 caliber or 38 caliber, 5.56 mm, 6 mm, 7 mm, 7.62 mm, 8 mm, 9 mm, 10 mm, or 12.7 mm. 
     
     
       10. The polymeric ammunition of  claim 1 , wherein the substantially cylindrical polymeric middle body is formed from a ductile polymer, a nylon polymer or a fiber-reinforced polymeric composite. 
     
     
       11. The polymeric ammunition of  claim 1 , wherein the substantially cylindrical polymeric bullet-end upper portion comprises a ductile polymer, a nylon polymer or a fiber-reinforced polymeric composite. 
     
     
       12. The polymeric ammunition of  claim 1 , wherein the substantially cylindrical polymeric middle body, the substantially cylindrical polymeric bullet-end upper portion or both independently comprise a polymers selected from the group consisting of polyurethane prepolymer, cellulose, fluoro-polymer, ethylene inter-polymer alloy elastomer, ethylene vinyl acetate, nylon, polyether imide, polyester elastomer, polyester sulfone, polyphenyl amide, polypropylene, polyvinylidene fluoride or thermoset polyurea elastomer, acrylics, homopolymers, acetates, copolymers, acrylonitrile-butadinen-styrene, thermoplastic fluoro polymers, inomers, polyamides, polyamide-imides, polyacrylates, polyatherketones, polyaryl-sulfones, polybenzimidazoles, polycarbonates, polybutylene, terephthalates, polyether imides, polyether sulfones, thermoplastic polyimides, thermoplastic polyurethanes, polyphenylene sulfides, polyethylene, polypropylene, polysulfones, polyvinylchlorides, styrene acrylonitriles, polystyrenes, polyphenylene, ether blends, styrene maleic anhydrides, polycarbonates, allyls, aminos, cyanates, epoxies, phenolics, unsaturated polyesters, bismaleimides, polyurethanes, silicones, vinylesters, urethane hybrids, polyphenylsulfones, copolymers of polyphenylsulfones with polyethersulfones or polysulfones, copolymers of poly-phenylsulfones with siloxanes, blends of polyphenylsulfones with polysiloxanes, poly(etherimide-siloxane) copolymers, blends of polyetherimides and polysiloxanes, and blends of polyetherimides and poly(etherimide-siloxane) copolymers. 
     
     
       13. The polymeric ammunition of  claim 1 , wherein the substantially cylindrical polymeric bullet-end and the substantially cylindrical polymeric bullet-end upper portion are welded or bonded together. 
     
     
       14. The polymeric ammunition of  claim 1 , wherein the projectile aperture further comprises a mechanical interlock adapted to mate to a groove on a bullet. 
     
     
       15. The polymeric ammunition of  claim 1 , wherein the substantially cylindrical polymeric bullet-end coupling element is welded or bonded to the substantially cylindrical polymeric bullet-end upper portion. 
     
     
       16. The polymeric ammunition of  claim 1 , wherein the primer insert comprises a polymer, a metal, an alloy, or a ceramic alloy. 
     
     
       17. The polymeric ammunition of  claim 1 , wherein the primer insert comprises the same material or different materials. 
     
     
       18. The polymeric ammunition of  claim 1 , wherein the primer insert comprises different polymers, different metals, different alloys, or different ceramic compositions. 
     
     
       19. The polymeric ammunition of  claim 1 , wherein the primer insert comprises steel, nickel, chromium, copper, carbon, iron, stainless steel or brass. 
     
     
       20. The polymeric ammunition of  claim 1 , wherein the primer insert comprises 102, 174, 201, 202, 300, 302, 303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 415, 416, 416R, 420, 430, 439, 440, 446 or 601-665 grade stainless steel or Ti6Al4V.